Synthesis and Characterization of Regenerated Cellulose Coated with a Silk Fibroin/Hydroxyapatite Scaffold for Enhanced Adhesion and Proliferation of Preosteoblast Cells

Biopolymer-based scaffolds are promising for tissue engineering due to their exceptional biocompatibility and biodegradability. This study synthesized biopolymer composite scaffolds involving regenerated cellulose extracted from sugarcane bagasse and silk fibroin (SF) at different concentrations. The scaffold was further coated with hydroxyapatite (HA) to evaluate its efficiency in promoting the growth of bone cells. The regenerated cellulose with HA and without SF was used as a control, and the scaffolds were characterized by various analytical techniques. The results from scanning electron microscopy showed a porous structure with a significant reduction in pore size from 220.04 ± 53.32 μm to 105.47 ± 27.68 μm, following the addition of 3% SF and HA coating. In addition, the percentage porosity and swelling properties decreased from 97.58 ± 0.25% and 1578.17 ± 94.17% to 92.29 ± 1.15% and 1213.36 ± 59.75%, respectively, for 3% SF and HA coating, with a biodegradation rate of 21.4 wt % in 28 days. The Brunauer–Emmett–Teller surface area decreased from 1.37 m2/g to 0.71 m2/g, while the compressive strength was increased from 8.28 ± 0.14 MPa to 20.46 ± 0.62 MPa. The scaffolds exhibited high viability of MC3T3-E1 preosteoblast cells (>85%), indicating no adverse cytotoxicity to the cells. The in vitro cell test also established that the scaffold supports bone cell proliferation (from 40% to 77.34%) in 7 days and protein adsorption. This was further confirmed by live/dead staining, cell adhesion, and morphology tests. These findings highlight the potential of regenerated cellulose-based scaffolds, functionalized with an SF/HA coating, for bone tissue engineering.